| 摘要 |
PURPOSE:To correct uneven which remains even after energy correction and linearity corrections by generating pulses at a frequency corresponding to a correction quantity and adding the pulses as an unblank signal at the position. CONSTITUTION:If a counted value is 98 at a certain position, the maximum value is considered to be 104 and the correction quantity corresponding to a deviation rate is 6. Then, the output of an adding circuit 54 is smaller than 100 as a threshold value up to 16 or the number of times of radiation incidence on the position, so the contents of a correction quantity total memory 52 only increase by 6 at every time at every number of times, but the output corresponding to the 17th incidence becomes 102 and exceeds 100, so a comparator 56 generates an output and a pulse generating circuit 50 generates a pulse, so that one extra unblank signal at the position is added. Consequently, the deviation from the maximum value is reduced to correct the uniformity.
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